Does this image have the 2.0 sources and if so is it workable for the DR800 as well?

The image is very old, so you need to do some updates yourself. The basics are explained here in the iOn Development Environment.pdf document from iRex. The development environment (compiler, Poky, Anjuta) is already installed, so you only need step 3, 4, 5 and 7.
In section 3.2.1.2 the intltoolize step is missing, you need to execute it to have a proper makefile in the /po-directory.
Source code for the firmware is here. (Although the firmware is called 2.0, the SDK/Sources for the latest software are in the 4.0 directory.)
The default configuration for the emulator in the SDK is DR800.